Researchers still are not sure why people with chronic fatigue syndrome suffer pain, exhaustion, anxiety, insomnia and other symptoms, sometimes for years. They have suspected viruses but have not proven which one. Joanne Silberner reports on what that uncertainty means for people living with the disease.

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Today, in "Your Health," we have two reports on chronic fatigue syndrome. We'll hear about possible treatments in a moment. First, we'll ask some questions about the cause. Researchers still are not sure why people suffer pain, exhaustion, anxiety, insomnia and other symptoms, sometimes for years. They have suspected viruses, but have not proven which one. Joanne Silberner reports on what that uncertainty means for people living with the disease.

JOANNE SILBERNER: Clinical psychologist Katrina Byrne of Seattle used to run, play racquetball, see patients and teach courses. That was before she developed chronic fatigue syndrome.

Ms. KATRINA BYRNE (Clinical Psychologist): There are days when I'm bedfast, and I get up only to use to the bathroom or get something to eat or drink. There are days when I'm housebound, and that's the most typical day for me right now.

SILBERNER: For the past 27 years, she's been prone to severe crashes -where she's sensitive to light and noise, and unable to read or watch TV.

Ms. BYRNE: Ill, like the way you feel when you have the flu - an unrelenting, unremitting flu.

SILBERNER: The first doctors Byrne went to weren't much help.

Ms. BYRNE: One doctor told me it was related to anxiety; another one said it was dehydration; a third one said it was hormonal; a fourth one said it was stress-related, and I needed to exercise.

SILBERNER: The problem back then was that no one much knew what was going on. With no known cause, there was no definitive lab test. There still isn't.

And Anthony Komaroff, a professor of medicine at Harvard Medical School, says that troubled doctors.

Mr. ANTHONY KOMAROFF (Harvard Medical School Medical Professor): I would say most doctors were very, very skeptical. First, this illness is defined, predominantly, by a group of symptoms, and so doctors were asking what's the evidence - objective evidence - that there's something physically wrong with these people?

SILBERNER: Over the years, researchers have identified various brain, immune system and energy metabolism irregularities. Komaroff points to a study done a couple of years ago by the Centers for Disease Control and Prevention. It showed that the majority of doctors now recognize chronic fatigue syndrome as an illness. Today, an estimated 1 million Americans are thought to have it.

But lots of regular folks are still doubters, at least in the experience of Cynthia Johnson of Lake Oswego, Oregon. She says the disbelief makes the disease worse. Johnson is a breast cancer survivor but in October 2009, she was hit with a bad flu that hasn't gone away.

Ms. CYNTHIA JOHNSON: People really admire you for fighting cancer, and they're very excited that you survived. They congratulate you for surviving. Nobody does that, day to day, for CFS. They are just like, oh.

SILBERNER: Just as she was diagnosed a couple of years ago, a report came out in a scientific journal linking a virus called XMRV to chronic fatigue syndrome. But 14 months later, four scientific papers claimed the virus was just a lab contaminant. Few in the field are hopeful that the cause has been discovered. The federal government is sponsoring two large studies that should answer the question once and for all.

For Katrina Byrne in Seattle and Cynthia Johnson in Portland, the initial report, even if it turns out to be a blind alley, did some good. Cynthia Johnson.

Ms. JOHNSON: I was happy to see all the attention in the press to XMRV, simply to bring attention to the disease. So my first thought was, at least people are writing about it.

SILBERNER: Johnson has been given a 50-50 chance by her doctor of throwing off the symptoms in a couple of years. She knows what she'll do if an effective treatment comes along.

Ms. JOHNSON: I'd like to make plans, you know, plan for the future, plan for tomorrow, and know that it would go well; to make an appointment for the doctors or a haircut or to meet friends, and be confident that I would feel reasonably well - you know, walk as far as I could, and go to the beach.

SILBERNER: Some changes are coming soon. The results of those two studies on whether there's an XMRV connection may be released at a meeting in Canada at the end of the month. Meanwhile, advocates for people with chronic fatigue syndrome are pushing for a name change, to make the syndrome sound like more than a description of someone who just needs a nap.

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